Edwaed weston



- f UNITED STATES PATENT OFFICE.

EDWARD WESTON, OE NEWARK, N. .i., ASSIGNOR To THE UNITED STATES EL oTEIo LIGHTING COMPANY, on NEW YORK, N. Y.

MANUFACTURE OF. C-ARBONS'FOR ELECTRIC LIGHTS.

. SPECIFICATION forming part of LettersPatent No. 264,988, dated September 26, 1882.

7 Application filed March 7, 1882. (No specimens.) I i To all whom it may concern Be it known that I,.EDWARD WESTON, a subject of the Queen of Great Britain, and a resident of Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvementsin the Manufacture ofGarbons for Electric Lights, of which the following is a specification.

In another application of even date herewith 10 I have described a conductor for incandescent lamps composed of structureless homogeneous carbon, and specified non-fibrous or amorphous cellulose as the material from which such carbons'may be produced. This substance in a 7 generally or commercially useful condition is obtained, as is set forth in said application, by the proper treatment or deoxidation of cellulose after having been brought to the conditions of the well-known collodion or celluloid. 2o Oarbons made from non-fibrous or amorphous cellulose as thus produced I have found to give results of the most satisfactory nature, which appear to be due mainly to their perfect homogeneity, density, and high specific resist- 25. auce. I have also found that serviceable carbons possessing in a measure these qualities A may be produced by another process of manufacture, in which homogeneous and practically amorphous cellulose is obtained, from which strips may becut'or stamped and carbonized. This process forms the subject of my present application.

It is well-known that a gelatinous substance may be produced by dissolving cellulose-for example, cotton, linen, or paper-with cupra ammonium, sulphuric acid, or other menstrua. This fact I take advantage of in the following manner: I first dissolve thoroughly any desirable quantity of cellulose in one or other of 40 the above-named solvents, and from the resultin g gelatinous substance I form sheets or strips in several ways, according to its consistency. 1f the proportion of the solvent used be small, I the sheets may be formed by passing the substance through rolls or by pressing it between flat plates. It produced in a more fluid state by using an increased proportion of solvent, the sheets are formed by pouring the solution on a flat surface, permittingit to spread. When above referred to.

the sheets have dried sufficiently to permit 0 handling they are washed with proper solutions to remove the non-volatile compounds used in the process of manufacture. If, for exam ple, cupra ammonium be the solvent used, a weak solution of ammonia should be employed, as it prevents precipitation of oxide of copper in the material. In case sulphuric acid be the solvent, an alkali, and preferably one thatis volatilesuch as ammonia-should be used to neutralize the acid and form sulphate of ammonia, which may be either washed out 7 or allowed to remain in, as it volatilizes when heat is applied. By this preparationhomogeneous sheets are formed that possess the same chemical characteristics as cellulose, in contra- 6 5 distinction to nitro-ceiiulose, and leave a residue on carbonization resembling in many respects the carbon described in my application From these sheets I cut, stamp, or otherwise form strips of the desired shape for the conductors of incandescentlamps, which I then carbonize in the manner described in my application of even date herewith, and mount and use them in any of the usual forms of incandescent lamp.

It may be stated that the blanks or strips may be cut from the sheets previously to the pnrifying pgocess described, and then immersed in the proper solutions.

V I do not wish to be understood as limiting 8o myself to the precise method of manufacturing the above-described substance or carbons, asthe same may be capable or numerous thoughimmaterial variations.

From the above it will appear that in the production of a homogeneous carbonizable'material from ordinary cellulose I may employ any solvent that destroys the fibrous structure of the cellulose withoutchang-ing the chemical condition, and leave it in a condition substano tially such as that described.

Cellulose thus treated or prepared differs from that described by me elsewhere as a com-- mercial article of manufacture, in that it is more or less brittle, opaque, and not as dense. 5

It forms, however, a valuable substance for the manufacture of carbon conductors, mainly for reasons herein specified.

Having now described my invention, What moving the impurities and non-volatile com- I claim is-- pounds therefrom, cutting, stamping, or other- 1. The method or process herein described wise forming from the sheets the blanks for the 15 of producing homogeneous carbonizable celluconductors, and earbonizing them, all as set 5 lose by dissolving fibrous cellulose, forming forth.

the solution or jelly into sheets, and treating In testimony whereof I have hereunto set the same for the removal of the acids and immy hand this 6th day of March, 1882.

purities, substantially as set forth. I r \I a 2. The method or process herein described EDWARD WDSIO [0 of manufacturing carbon conductors forincan- \Vitnesses:

descent lamps by dissolving fibrous cellulose, HENRY A. BEOKMEYER,

forming the solution or jelly into sheets, re- JOHN 1. DENGLER. 

